IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION, VOL. 15, NO. 3, JUNE 1999 1 Book Reviews

Virtual Reality Technology--G. Burdea and Ph. Coiffet

(New York: Wiley, 1994, pp. 400.) Reviewed by A. K. Bejczy

Virtual Reality Technology is a welcome book contribution to
theengineering literature. It offers an authentic and below-the
surface explanation of and insight into this fascinating and rapidly
evolving field of technology. In the Introduction the authors
immediatelyemphasize that virtual reality (VR) technology includes far
more than some computer graphics generated and realistic looking
simulation of world scenarios, though computer graphics plays a key
visualizationrole in the manifestation of VR technology
products. According to the authors, equally important elements of this
technology are three big "I" capabilities:
Immersion-Interaction-Imagination. Immersion-Interaction is a twin
element and denotes the VR users' capability to interact with the
simulated world scenarios through all human sensory and motoric input
and output channels. The third big "I" element,Imagination, has some
artistic undertone, but--according to the authors--it essentially
relates to the human imaginative inventiveness that searches and finds
valuable applications for VR technology,applications that address and
solve particular real problems in engineering, medicine, and so on.

Following the Introduction, which also tells a brief history ofVR
technology, the book content is distributed in eight chapters.  The
first chapter describes VR Tools which include 3-D position sensors,
trackballs, sensing gloves, stereo viewing devices, 3-D
soundgenerators and their evaluation. The next chapter is dedicated to
Touch and Force Feedback, a new and exciting augmentation of VR
interface techniques. The next chapter discusses the Computing
Architectures that are needed to satisfy the real-time computational
demands of VR simulations. The subsequent chapter deals with Modeling
including geometric, kinematic and physical modeling and The reviewer
is with the Jet Propulsion Laboratory, California Institute
ofTechnology, Pasadena, CA 91109 USA. Publisher Item Identifier S
1042-296X(99)03545-4.  model segmentation. The following chapter is
dedicated to Programming in VR which includes the description of
powerful programmingpackages such as "WorldTookKit" or "Amaze"
constructed to help VR application developers. This chapter also
contains over 20 highquality color illustrations and lists a few
noncommercial VR toolkitsthat support less expensive I/O devices, but
provide less performance graphics. They are, however, useful for
proof-of-concept in initial stages of R&D work. The next chapter deals
with Human Factors in VR, including VR evaluation methodologies which
are only in the emerging stage. In this chapter, the authors also
discuss the VR and society relation as VR may impact the professional,
private and publiclife. The next to last chapter is about
Applications, and occupies nearly 80 pages. The authors discuss the
applications in five major domains:

        1) medicine and rehabilitation;
        2) entertainment, arts, and education;
        3) military and aerospace; 
        4) business;
        5) robotics and manufacturing.

It becomes very clear at the end of this chapter that application of
VR technology can improve design and training procedures and can lead
to performance effectiveness that could not be achieved
before. Thelast chapter is about The Future. Here the authors look at
envisioned new components of VR technology like large volume tracking,
new visual and haptic displays, neural interfaces, "image gloves,"
voicecontrol, and portable computers. This chapter concludes with a
desire that in the future programming and modeling standards will be
developed, primarily to allow large scale networking of
numerouscomputing platforms of various hardware architectures.

The book is augmented with a useful list of bibliography on 25 pages
and a list of companies and research laboratories involved inVR
technology development.

The book can be recommended not only to the curious beginners, but
also to the practitioners since it offers a well-integrated overviewof
VR technology as a whole in the mid-1990's.

(C) 1999 IEEE


BOOK REVIEW
"VR News," UK, Vol. 5, No. 7, page 32, 1996.

Force and Touch Feedback for Virtual Reality

Grigore Burdea
John Wiley & Sons, Inc.:  1996
ISBN 0-471-02141-5


At last, a book completely devoted to haptics.  Haptics researchers have   
been forced to choose between two courses of action:  to laboriously   
collect paper after paper from sources well-known and obscure, or to   
remain blissfully ignorant of the work of their peers.  For those with a   
mentor or two, taking the high road was much easier, but for others it   
was a daunting challenge.  Now, for the price of a book, Greg Burdea has   
tackled much of the challenge for us.

Burdea's first book on virtual reality, Virtual Reality Technology (with   
P. Coiffet, VR News review June 1995) offered broad coverage of VR   
technologies, with a chapter on force and touch feedback.  Such books   
offer more enlightenment to the reader on topics outside his or her   
specialization than within it.  What I hungered for was a resource that   
would put years of accumulated haptics knowledge in one place, contain a   
few nuggets that I'd overlooked in my searching, and offer enough clarity   
and completeness that I could simply hand it to a newcomer in my   
laboratory with the imperative, "read this."

A few book chapters have emerged as valuable references, but this book is   
the first to sate my desire.  The book is almost two books in one:  a   
diligent coverage of the basic issues in force and touch feedback, and an   
exhaustive review of the state of the art.  While state-of-the-art   
reviews have temporal limitations, the good ones define a common starting   
point for future effort and age gracefully into historical references.

The book begins with the basics, giving a brief historical perspective,   
leading into a discussion of human haptic sensing and control issues.   
The chapter on actuators will be especially useful to those without a   
mechanics background.  The next few chapters detail the state of the art.   
The latter third of the book examines what can be done with knowledge   
and hardware.  It addresses the important questions of how to program   
virtual environments with haptic qualities and how to control haptic   
devices to present the forces generated by those environments.  The human   
factors chapter introduces some basic methods of performance measurement   
and covers some notable papers, though as with other facets of this book,   
a reader searching for deep understanding will still need to refer to the   
source material.  A chapter on applications gives an exciting taste of   
the possibilities for haptics, with a bias towards medical uses.  The   
final chapter projects future developments, concentrating on two   
constraints of present day haptics:  the relative scarcity of suitable   
actuators and the tendency of feedback devices to tie the user to one   
spot.

One concern I have is the relative immaturity of the information   
available to guide device designers.  The field has certainly not   
progressed to the stage that a "designer's cookbook" is possible.  The   
various tables and summaries in the book should be interpreted carefully,   
and performance figures should be checked for relevance to any intended   
application.  It's still an imperfect world, so practical designers will   
have to make do with a good book that's not quite a design guide, or hold   
their breath and plunge into the more than 20 pages of references at the   
back of the book.

A few other nice features of this book deserve mention.  Burdea makes   
excellent use of figures (drawings, photographs, and charts), and   
includes eight pages of attractive color plates.  Another ten pages list   
companies and research laboratories around the world, with phone numbers,   
postal, and e-mail addresses.  A listing of relevant Web sites would have   
been nice, but these can always be obtained through the e-mails or by   
visiting the Haptics Community Web page at http://haptic.mech.nwu.edu/.

If you have any desire to have much of your accumulated haptics   
information gathered in one place, to find out if there's anything that   
you've missed, or have a need to introduce newcomers to haptics, then   
this book should be in your library.  Hopefully, a second edition will   
follow in a few years as the rapid progress in research and commercial   
haptics makes more mature design information available and concrete   
wage-earning applications make their place amidst demonstration projects   
and speculation.

Christopher Hasser, September 1996

Christopher Hasser received his MS in Electrical Engineering while at the USAF 
Armstrong Laboratory.  He has over five years experience with force and 
tactile feedback devices as a researcher and research manager.  During 
that time he managed SBIR contracts, headed the Human Sensory Feedback and 
Telepresence Project, and became recognized as the Air Force expert
on haptic feedback issues.  He has published extensively, and has coauthored 
a book chapter on haptic feedback (The Haptic Illusion, in "The Digital 
Illusion," ed. Clark-Dodsworth, ACM/Addison-Wesley, in press). In June 1966 
Christopher joined Immersion Corporation as Chief Research Engineer. 
He can be reached at c.hasser@ieee.org or http://www.immerse.com.


BOOK REVIEW
Building and Feeling Virtual Worlds
By Ben Delaney
CyberEdge Journal, October 1996.

Feeling virtual worlds

* * * * * (5 stars rating)

One of the most common complaints about virtual world experiences is
that the lack of physical sensations in the environment. Visual
simulation is nearing photographic quality, and 3D sound is very
convincing. But as soon as one touches a virtual object, or picks up
a virtual car and tosses it into the next simulation, one has a great
sense of incompleteness. "Why", the question is often asked, "can't I
feel anything in this great virtual reality?"

There is no easy answer to that question, despite the millions of
dollars and thousands of hours spent trying to understand and
duplicate our incredibly subtle and complex haptic senses. However,
at last, we can at least understand the magnitude of the problem, and
the state of the art. Grigore Burdea, an Associate Professor at the
CAIP Center of Rutgers University, spent most of last year engaged in
research and writing about this missing dimension of VR. His new
book, Force and Touch Feedback for Virtual Reality, is the result of
that effort. As far as I know, there is no more complete or erudite
book on the subject. 

Burdea careful lays the groundwork for his survey of force feedback
(resistive impulses, FFB) and tactile feedback (sensations of
texture, temperature, etc., TFB) devices and concepts by providing a
thorough background in human proprioception. He shares with the
reader the fruits of his research: how the various receptors in the
skin, muscles, bones and joints interact, how the nervous system
perceives and conveys haptic data, reaction times and bandwidths of
human response, and much more. He describes studies on the resolution
of feeling, the average strength of various parts of the body, and
time to fatigue. All in all, one is left with the impression that
Burdea is a man with a good feel for the subject.


Interestingly, reading this book made me all the more pessimistic
regarding our likelihood of ever having good FFB devices for general
use. The problem is manifold. As Burdea points out, the range of
forces that human beings are capable of feeling and reacting to is
great. It spans several orders of magnitude, from the gentle caress of
a lover brushing away a strand of hair, to the rough effort required
to push a recalcitrant automobile. Designing one device, even a hybrid
device, to duplicate this range of force is a daunting concept.
Furthermore, FFB devices must be grounded. That is, they must have
something to push against. A portable FFB device would necessarily be
of limited scope.

The outlook for TFB devices is much better. Because these devices are
not resistive in nature, they can (indeed, should be) small and
portable. A glove with an inner surface made of nano-mechanical
effectors is conceivable, and could possibly provide realistic
sensations of friction, slippage, texture, and other sensations.
However, the likelihood of such a device being built in the next few
years is slim. 

Lacking any ideal solution, many experimenters and manufacturers,
Burdea among them, have developed limited force and tactile feedback
devices. Many such devices, such as the (CJ-winning) Phantom, and the
Impulse Engine, are commercially available and are finding acceptance
in specialty applications. Most people in the VR business are
familiar with the GROPE experiment carried out at UNC chapel Hill, in
which a large FFB arm, designed for working with radioactive
materiel, has been used to evaluate the value of FFB in molecular
docking research. Medical simulation is an important use of FFB, and
gamers are starting to see low-cost devices built into joysticks and
other controllers. All of this, and a great deal more, is carefully
covered in this book.

Were I giving a course in haptic simulation, this would be my text of
choice. I recommend it without reservation to anyone considering
adding haptic feedback to a simulation. If you haven't covered this
material, you would need  a lot of time to catch up. Luckily, Burdea
has done it for us. 

Force and Touch Feedback for Virtual Reality, by Grigore Burdea.
Published by John Wiley & Sons, New York, NY, USA. ISBN:
0-471-02141-5, hard cover, illustrated, indexed, us$54.95.